<?php
/**
 * CBaseListView class file.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @link http://www.yiiframework.com/
 * @copyright Copyright &copy; 2008-2011 Yii Software LLC
 * @license http://www.yiiframework.com/license/
 */

/**
 * CBaseListView is the base class for {@link CListView} and {@link CGridView}.
 *
 * CBaseListView implements the common features needed by a view wiget for rendering multiple models.
 *
 * @author Qiang Xue <qiang.xue@gmail.com>
 * @version $Id: CBaseListView.php 3101 2011-03-22 17:35:19Z qiang.xue $
 * @package zii.widgets
 * @since 1.1
 */
abstract class CBaseListView extends CWidget
{
    /**
     * @var IDataProvider the data provider for the view.
     */
    public $dataProvider;
    /**
     * @var string the tag name for the view container. Defaults to 'div'.
     */
    public $tagName='div';
    /**
     * @var array the HTML options for the view container tag.
     */
    public $htmlOptions=array();
    /**
     * @var boolean whether to enable sorting. Note that if the {@link IDataProvider::sort} property
     * of {@link dataProvider} is false, this will be treated as false as well. When sorting is enabled,
     * sortable columns will have their headers clickable to trigger sorting along that column.
     * Defaults to true.
     * @see sortableAttributes
     */
    public $enableSorting=true;
    /**
     * @var boolean whether to enable pagination. Note that if the {@link IDataProvider::pagination} property
     * of {@link dataProvider} is false, this will be treated as false as well. When pagination is enabled,
     * a pager will be displayed in the view so that it can trigger pagination of the data display.
     * Defaults to true.
     */
    public $enablePagination=true;
    /**
     * @var array the configuration for the pager. Defaults to <code>array('class'=>'CLinkPager')</code>.
     * @see enablePagination
     */
    public $pager=array('class'=>'CLinkPager');
    /**
     * @var string the template to be used to control the layout of various sections in the view.
     * These tokens are recognized: {summary}, {items} and {pager}. They will be replaced with the
     * summary text, the items, and the pager.
     */
    public $template="{summary}\n{items}\n{pager}";
    /**
     * @var string the summary text template for the view. These tokens are recognized and will be replaced
     * with the corresponding values:
     * <ul>
     *   <li>{start}: the starting row number (1-based) currently being displayed</li>
     *   <li>{end}: the ending row number (1-based) currently being displayed</li>
     *   <li>{count}: the total number of rows</li>
     *   <li>{page}: the page number (1-based) current being displayed, available since version 1.1.3</li>
     *   <li>{pages}: the total number of pages, available since version 1.1.3</li>
     * </ul>
     */
    public $summaryText;
    /**
     * @var string the message to be displayed when {@link dataProvider} does not have any data.
     */
    public $emptyText;
    /**
     * @var string the CSS class name for the container of all data item display. Defaults to 'items'.
     */
    public $itemsCssClass='items';
    /**
     * @var string the CSS class name for the summary text container. Defaults to 'summary'.
     */
    public $summaryCssClass='summary';
    /**
     * @var string the CSS class name for the pager container. Defaults to 'pager'.
     */
    public $pagerCssClass='pager';
    /**
     * @var string the CSS class name that will be assigned to the widget container element
     * when the widget is updating its content via AJAX. Defaults to 'loading'.
     * @since 1.1.1
     */
    public $loadingCssClass='loading';

    /**
     * Initializes the view.
     * This method will initialize required property values and instantiate {@link columns} objects.
     */
    public function init()
    {
        if($this->dataProvider===null)
        throw new CException(Yii::t('zii','The "dataProvider" property cannot be empty.'));

        $this->dataProvider->getData();

        $this->htmlOptions['id']=$this->getId();

        if($this->enableSorting && $this->dataProvider->getSort()===false)
        $this->enableSorting=false;
        if($this->enablePagination && $this->dataProvider->getPagination()===false)
        $this->enablePagination=false;
    }

    /**
     * Renders the view.
     * This is the main entry of the whole view rendering.
     * Child classes should mainly override {@link renderContent} method.
     */
    public function run()
    {
        $this->registerClientScript();

        echo CHtml::openTag($this->tagName,$this->htmlOptions)."\n";

        $this->renderContent();
        $this->renderKeys();

        echo CHtml::closeTag($this->tagName);
    }

    /**
     * Renders the main content of the view.
     * The content is divided into sections, such as summary, items, pager.
     * Each section is rendered by a method named as "renderXyz", where "Xyz" is the section name.
     * The rendering results will replace the corresponding placeholders in {@link template}.
     */
    public function renderContent()
    {
        ob_start();
        echo preg_replace_callback("/{(\w+)}/",array($this,'renderSection'),$this->template);
        ob_end_flush();
    }

    /**
     * Renders a section.
     * This method is invoked by {@link renderContent} for every placeholder found in {@link template}.
     * It should return the rendering result that would replace the placeholder.
     * @param array $matches the matches, where $matches[0] represents the whole placeholder,
     * while $matches[1] contains the name of the matched placeholder.
     * @return string the rendering result of the section
     */
    protected function renderSection($matches)
    {
        $method='render'.$matches[1];
        if(method_exists($this,$method))
        {
            $this->$method();
            $html=ob_get_contents();
            ob_clean();
            return $html;
        }
        else
        return $matches[0];
    }

    /**
     * Renders the empty message when there is no data.
     */
    public function renderEmptyText()
    {
        $emptyText=$this->emptyText===null ? Yii::t('zii','No results found.') : $this->emptyText;
        echo CHtml::tag('span', array('class'=>'empty'), $emptyText);
    }

    /**
     * Renders the key values of the data in a hidden tag.
     */
    public function renderKeys()
    {
        echo CHtml::openTag('div',array(
			'class'=>'keys',
			'style'=>'display:none',
			'title'=>Yii::app()->getRequest()->getUrl(),
        ));
        foreach($this->dataProvider->getKeys() as $key)
        echo "<span>".CHtml::encode($key)."</span>";
        echo "</div>\n";
    }

    /**
     * Renders the summary text.
     */
    public function renderSummary()
    {
        if(($count=$this->dataProvider->getItemCount())<=0)
        return;

        echo '<div class="'.$this->summaryCssClass.'">';
        if($this->enablePagination)
        {
            if(($summaryText=$this->summaryText)===null)
            $summaryText=Yii::t('zii','Displaying {start}-{end} of {count} result(s).');
            $pagination=$this->dataProvider->getPagination();
            $total=$this->dataProvider->getTotalItemCount();
            $start=$pagination->currentPage*$pagination->pageSize+1;
            $end=$start+$count-1;
            if($end>$total)
            {
                $end=$total;
                $start=$end-$count+1;
            }
            echo strtr($summaryText,array(
				'{start}'=>$start,
				'{end}'=>$end,
				'{count}'=>$total,
				'{page}'=>$pagination->currentPage+1,
				'{pages}'=>$pagination->pageCount,
            ));
        }
        else
        {
            if(($summaryText=$this->summaryText)===null)
            $summaryText=Yii::t('zii','Total {count} result(s).');
            echo strtr($summaryText,array(
				'{count}'=>$count,
				'{start}'=>1,
				'{end}'=>$count,
				'{page}'=>1,
				'{pages}'=>1,
            ));
        }
        echo '</div>';
    }

    /**
     * Renders the pager.
     */
    public function renderPager()
    {
        if(!$this->enablePagination)
        return;

        $pager=array();
        $class='CLinkPager';
        if(is_string($this->pager))
        $class=$this->pager;
        else if(is_array($this->pager))
        {
            $pager=$this->pager;
            if(isset($pager['class']))
            {
                $class=$pager['class'];
                unset($pager['class']);
            }
        }
        $pager['pages']=$this->dataProvider->getPagination();

        if($pager['pages']->getPageCount()>1)
        {
            echo '<div class="'.$this->pagerCssClass.'">';
            $this->widget($class,$pager);
            echo '</div>';
        }
        else
        $this->widget($class,$pager);
    }

    /**
     * Registers necessary client scripts.
     * This method is invoked by {@link run}.
     * Child classes may override this method to register customized client scripts.
     */
    public function registerClientScript()
    {
    }

    /**
     * Renders the data items for the view.
     * Each item is corresponding to a single data model instance.
     * Child classes should override this method to provide the actual item rendering logic.
     */
    abstract public function renderItems();
}
